4.11.4.3 Compile

This is meant to handle compiling or building a project written in C.
The default command is make all. When the compile is finished,
the log file is scanned for GCC warning messages, a summary log is
created with any problems that were seen, and the step is marked as
WARNINGS if any were discovered. Through the WarningCountingShellCommand
superclass, the number of warnings is stored in a Build Property named
“warnings-count”, which is accumulated over all Compile steps (so if two
warnings are found in one step, and three are found in another step, the
overall build will have a “warnings-count” property of 5).

The default regular expression used to detect a warning is
'.*warning[: ].*' , which is fairly liberal and may cause
false-positives. To use a different regexp, provide a
warningPattern= argument, or use a subclass which sets the
warningPattern attribute:

The warningPattern= can also be a pre-compiled python regexp
object: this makes it possible to add flags like re.I (to use
case-insensitive matching).

Note that the compiled warningPattern will have its match method
called, which is subtly different from a search. Your regular
expression must match the from the beginning of the line. This means that to
look for the word "warning" in the middle of a line, you will need to
prepend '.*' to your regular expression.

The suppressionFile= argument can be specified as the (relative) path
of a file inside the workdir defining warnings to be suppressed from the
warning counting and log file. The file will be uploaded to the master from
the slave before compiling, and any warning matched by a line in the
suppression file will be ignored. This is useful to accept certain warnings
(eg. in some special module of the source tree or in cases where the compiler
is being particularly stupid), yet still be able to easily detect and fix the
introduction of new warnings.

The file must contain one line per pattern of warnings to ignore. Empty lines
and lines beginning with # are ignored. Other lines must consist of a
regexp matching the file name, followed by a colon (:), followed by a
regexp matching the text of the warning. Optionally this may be followed by
another colon and a line number range. For example:

If no line number range is specified, the pattern matches the whole file; if
only one number is given it matches only on that line.

The default warningPattern regexp only matches the warning text, so line
numbers and file names are ignored. To enable line number and file name
matching, privide a different regexp and provide a function (callable) as the
argument of warningExtractor=. The function is called with three
arguments: the BuildStep object, the line in the log file with the warning,
and the SRE_Match object of the regexp search for warningPattern. It
should return a tuple (filename, linenumber, warning_test). For
example:

(Compile.warnExtractFromRegexpGroups is a pre-defined function that
returns the filename, linenumber, and text from groups (1,2,3) of the regexp
match).

In projects with source files in multiple directories, it is possible to get
full path names for file names matched in the suppression file, as long as the
build command outputs the names of directories as they are entered into and
left again. For this, specify regexps for the arguments
directoryEnterPattern= and directoryLeavePattern=. The
directoryEnterPattern= regexp should return the name of the directory
entered into in the first matched group. The defaults, which are suitable for
GNU Make, are these: